1 //===- PtrUseVisitor.cpp - InstVisitors over a pointers uses --------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 /// \file
10 /// Implementation of the pointer use visitors.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "llvm/Analysis/PtrUseVisitor.h"
15 #include "llvm/IR/Instruction.h"
16 #include "llvm/IR/Instructions.h"
17 
18 using namespace llvm;
19 
enqueueUsers(Instruction & I)20 void detail::PtrUseVisitorBase::enqueueUsers(Instruction &I) {
21   for (Use &U : I.uses()) {
22     if (VisitedUses.insert(&U).second) {
23       UseToVisit NewU = {
24         UseToVisit::UseAndIsOffsetKnownPair(&U, IsOffsetKnown),
25         Offset
26       };
27       Worklist.push_back(std::move(NewU));
28     }
29   }
30 }
31 
adjustOffsetForGEP(GetElementPtrInst & GEPI)32 bool detail::PtrUseVisitorBase::adjustOffsetForGEP(GetElementPtrInst &GEPI) {
33   if (!IsOffsetKnown)
34     return false;
35 
36   APInt TmpOffset(DL.getIndexTypeSizeInBits(GEPI.getType()), 0);
37   if (GEPI.accumulateConstantOffset(DL, TmpOffset)) {
38     Offset += TmpOffset.sextOrTrunc(Offset.getBitWidth());
39     return true;
40   }
41 
42   return false;
43 }
44